ASPREE-XT BI-NATIONAL ADMINISTRATIVE CORE ? SUMMARY / ABSTRACT The ASPirin in Reducing Events in the Elderly (ASPREE) study successfully established a cohort of 19,114 healthy older adults in the U.S. and Australia who were free of Alzheimer?s disease and related dementias (ADRD), cardiovascular disease, and significant physical disability at baseline, and tested whether the exposure to 5 years of low-dose aspirin (LDA) would prolong dementia-free and disability-free survival. Although the intervention period has ended, the establishment of this large and diverse cohort, coupled with unprecedented findings from the intervention period, has created a rare opportunity for continued surveillance of important health outcomes and the antecedents that jeopardize disability-free survival in this aging population; especially ADRD and cancer. Personal health information will be collected annually from participants, and major clinical events will be confirmed through case documentation prepared for expert adjudication of ADRD (and sub-type classification into Alzheimer?s disease and non- ADRD), cancer (incident, metastatic, type, stage and death), and other key health outcomes including death. Observational follow-up of large, long-term aging studies such as ASPREE benefit from continuity, experience and leadership with ADRD expertise. In this funding request, the ASPREE leadership team proposes to extend follow-up of the participants in both the U.S. and Australia for an additional five years (i.e., ?ASPREE-XT?), which will greatly enrich an already unique, and highly valuable international research asset focused on prolonging healthy independent life in the elderly, free of dementia and disability. The infrastructure needed to accomplish this will rely on the continuity, leadership, and experience of the U.S. and Australian Coordinating Centers that have proven their success in the ASPREE trial through the exemplary study conduct and completion. This includes bi-national standardized training and accreditation to ensure the consistent administration of the annual cognitive battery and triggered dementia assessments which include the Alzheimer's Disease Assessment Scale cognitive subscale. The Bi-National Administrative Core will deploy the infrastructure and governance necessary to accomplish the aims of the ASPREE-XT longitudinal cohort study, including to understand the legacy effects of low dose aspirin on cognitive decline, ADRD, disability and cancer prevention. The overarching goal of the Bi-National Administrative Core is to foster the dynamic exchange of information, ideas, and data arising from all Cores to provide insight into factors that may extend dementia-free and disability-free survival of older adults.